Tom Holland’s back, swinging like his old self … ’cause we have the first sighting on the “Spider-Man: Brand New Day” set since that scary concussion sent him to the ER.

Peep the clip — Tom was fully back in action in London Thursday, diving into a major scene while the crew watched him web-sling back to form.

No Spidey suit yet, but Tom was all in during the rehearsal — script in hand, scheming the scene, chasing that perfect web-slinging moment.

Filming’s back on after Tom’s mild concussion-stunt scare in late September … no extra deets, but all signs point to Spider-Man being A-OK!